Food & Cooking Recipes Healthy Recipes Vegetarian Recipes Black-Bean Burgers with Pickled Onions 3.6 (7) By Martha Stewart Editors Martha Stewart Editors Facebook Instagram Twitter Website An article attributed to "Martha Stewart Editors" indicates when several writers and editors have contributed to an article over the years. These collaborations allow us to provide you with the most accurate, up-to-date, and comprehensive information available.The Martha Stewart team aims to teach and inspire readers daily with tested-until-perfected recipes, creative DIY projects, and elevated home and entertaining ideas. They are experts in their fields who research, create, and test the best ways to help readers design the life they want. The joy is in the doing. Editorial Guidelines Updated on May 16, 2017 Print Share Share Tweet Pin Email Servings: 4 Trying to work meatless meals into your routine? A pot of hearty, healthy Cuban Black Beans makes a satisfying dish -- and enough leftovers for this recipe. Ingredients 1 teaspoon plus 1 tablespoon extra-virgin olive oil 1 small red onion, thinly sliced 1 teaspoon sugar 2 tablespoons red-wine vinegar Coarse salt and ground pepper 4 cups cooked black beans, drained (reserved from Cuban Black Beans) 1 small red bell pepper, finely chopped ¼ cup roughly chopped fresh cilantro ¾ cup dried breadcrumbs 1 large egg, lightly beaten 3 tablespoons mayonnaise 4 toasted kaiser rolls Thinly sliced avocado Directions In a medium nonstick skillet, heat 1 teaspoon oil over medium. Add red onion and cook 1 minute. Add sugar and cook until dissolved. Add vinegar and season with salt and pepper. Transfer onion mixture to a small bowl and wipe out skillet. In a large bowl, mash 2 1/2 cups beans. Stir in bell pepper, cilantro, breadcrumbs, egg, and 1 1/2 cups beans. Season with 1/2 teaspoon salt and 1/4 teaspoon pepper and form mixture into 4 patties. Heat 1 tablespoon oil over medium-high. Cook 2 patties until crisp on outside and heated through, about 5 minutes, flipping once. Repeat with more oil and remaining patties. Spread mayonnaise on rolls; top with burgers, avocado, and onion mixture. Print